1. Field of the Invention
The present invention relates to a wireless power transmitting apparatus and method of selecting at least one of one central coil disposed at the center of a core and two side coils each disposed at left and right sides of the core as a power transmitting coil according to a position at which a power receiving apparatus is positioned and wirelessly transmitting a power to the power receiving apparatus.
2. Description of the Related Art
Generally, various portable terminals such as a cellular phone, a personal digital assistant, and the like, have been mounted with a power receiving apparatus supplying an operation power thereto.
The power receiving apparatus, which is charged with a power supplied from an external charging apparatus and supplies the charged power as an operation power to the portable terminal to operate the portable terminal, may include a battery cell module charged with the power, a charging and discharging circuit inputting the power supplied from the external charging apparatus to charge the power in the battery cell module and discharging the power charged in the battery cell module to supply the discharged power as the operation power to the portable terminal, and the like.
As a scheme of electrically connecting the charging apparatus to the power receiving apparatus, a terminal connection scheme of directly connecting a terminal through which the power is output in the charging apparatus and a terminal to which the power is input in the power receiving apparatus to each other through a cable, a connector, and the like, has been known.
In the terminal connection scheme, the terminal of the charging apparatus and the terminal of the power receiving apparatus have the different potential difference.
Therefore, in the case in which the terminal of the charging apparatus and the terminal of the power receiving apparatus are connected to each other or disconnected from each other, an instantaneous discharging phenomenon may occur.
This instantaneous discharging phenomenon causes abrasion of the terminal of the charging apparatus and the terminal of the power receiving apparatus. In addition, in the case in which foreign materials are accumulated in the terminal of the charging apparatus and the terminal of the power receiving apparatus, the heat may occur in the foreign materials due to the instantaneous discharging phenomenon, so there is a risk that an accident such as a fire, or the like, will occur.
In addition, the power charged in the battery cell module charged in the power receiving apparatus is naturally discharged to the outside through the terminal of the power receiving apparatus due to moisture, or the like, so a lifespan of the power receiving apparatus may be decreased and performance of the power receiving apparatus may be deteriorated.
Recently, a wireless power transmitting apparatus wirelessly transmitting the power to the power receiving apparatus has been suggested in order to solve several problems of the terminal connection scheme as described above.
The wireless power transmitting apparatus wirelessly transmits the power in, for example, an electromagnetic induction scheme. In addition, the power receiving apparatus receives the power wirelessly transmitted by the wireless power transmitting apparatus and charges the received power in the battery cell module.
A number of efforts have been conducted in order for the wireless power transmitting apparatus to wirelessly transmit the power stably at high efficiency and in order for the power receiving apparatus to receive the power transmitted by the wireless power transmitting apparatus as much as possible to charge the power in the battery cell module.
Since coupling between terminals is not made between the wireless power transmitting apparatus and the power receiving apparatus, it is required for the power receiving apparatus to be positioned at a charging position of a charger included in the wireless power transmitting apparatus.
However, a case in which a user does not position the power receiving apparatus at the charging position of the charger has frequently occurred. In addition, even though the user positions the power receiving apparatus at the normal position of the charger, when vibration is generated in the portable terminal mounted with the power receiving apparatus due to reception of a call signal, or the like, a case in which the power receiving apparatus moves to deviate from the charging position has frequently occurred